1. Field of the Invention
The present invention relates to an optical module for a photographing apparatus. More particularly, the present invention relates to an optical module for a photographing apparatus having a simple, efficiently configured structure.
2. Description of the Related Art
Photographing apparatus such as digital still cameras and digital video cameras are widely used. These type of photographing apparatus generally include an optical system having a lens unit, an imaging device arranged at a side of the lens unit, an image processing unit processing an electric signal received from the imaging device, and a memory storing a photographed image.
In the operation of the photographing apparatus, when a photographer photographs an object, image light of the object passes through the lens unit is incident on the imaging device such as a CCD (charge coupled device). The imaging device converts incident image light to an electric image signal. The image processing unit processes the image signal. The memory stores the photographed image. Thus, the photographing is complete.
For the convenience of a user, a zoom lens optical system is used to photograph an object at a wide angle or zoom in a remote object. The zoom lens optical system has a mechanical structure to change the distance between zoom lens groups constituting the zoom lens optical system, thereby performing a multiplication change function.
In a conventional zoom lens optical system, a solid cam (3D cam) formed on a cylindrical barrel is generally provided as a mechanical structure to change the distance between the zoom lens groups. However, the solid cam is difficult to manufacture and is time consuming and costly to assemble. Also, the conventional system typically includes a structure in which the zoom lens groups move along the solid cam in the barrel during a zoom operation. Thus, the positions at which a zoom motor and a focusing motor can be arranged around the solid cam are limited, thus making it difficult to efficiently use the space in the barrel and increasing the overall size of an overall optical module.